CCND2 and seminoma: Among them, we found the cell cycle- and CDK4/6-associated genes CCND2 (seminomas 9.8%, non-seminomas 16.8%), CDKN1B (P27; seminomas 15.3%, non-seminomas 16.4%) and MDM2 (seminomas 4%, non-seminomas 3.6%) commonly amplified in seminomas and non-seminomas (Supplementary data S1A).